Study On The Key Technology Of Flexible Machining System Based On The 6-DOF Robot

In this paper, the flexible manufacturing system of 6-DOF arc welding robot was used as the research object, a series of modeling?simulation and experiment are carried out to improve the precision of the trajectory and the welding quality. First, to make kinematical modeling with the use of D-H parametric method, and solve the obverse and inverse kinematics, and the multi-solution problem of inverse kinematics was analyzed and the project design was optimized based on the shortest route principle, then work space analysis was made about the robot with the use of Monte Carlo method.Based on the Kane method, the dynamics modeling of the robot was made,and the graphical modeling was made for the robot by using SIMULINK, and the dynamic simulation of the robot was carried out in MATLAB and SIMULINK.Through comparative analysis of the simulation results, the correctness of the two models was mutually confirmed. And then the SIMULINK model was used to simulate the initial conditions of each joint drive to make the theoretical model guide the actual production. Based on the shortest route criterion inverse kinematics optimization scheme, the least moment criterion was added, to design the inverse kinematics optimization scheme of robot kinematics.Based on the kinematics model built, the error model suitable for the calibration technique of arc welding robot was deduced. Analysis was made of the error sources affecting the absolute positioning accuracy of robots, and then the simulation scheme design of error model was made, and then the validity of error model built was verified by simulating a group of simulation experimental data.According to the detection specification and requirements of positional accuracy in the international standard, the experimental platform was set up, which was composed of robot body, laser tracker, measurement target sphere and other relevant devices. The base coordinate system calibration method of the robot calibration method was designed based on the dual quaternion algorithm, and the base coordinate system calibration experiment was completed. The robot tool coordinate system closed loop testing system was established with the use of equal distance of space geometry method, to complete the tool coordinate system calibration rapidly, in the meanwhile, the geometric parameters calibration of the robot body was made on the experimental platform, and the geometric parameter error was identified and compensated through the optimization method, then the validity of calibration results was verified through experiment.Finally, through the combination of the work space analysis of the robot, error model establishment and kinematic parameter calibration, and the error distribution in the work space was simulated in MATLAB, so as to guide the actual production.